Residential / Light Commercial
Gas Tankless Water Heaters
TANKLESS HIGH EFFICIENCY
CONDENSING INDOOR MODELS
FEATURES
CONDENSING TECHNOLOGY PROVIDES SIGNIFICANT ENERGY COST SAVINGS
PRIMARY HEAT EXCHANGER IS CONSTRUCTED OF HRS35 COMMERCIALGRADE COPPER
■ Stronger than standard copper and more resilient against erosion
SECONDARY HEAT EXCHANGER IS MADE OF TYPE 316L STAINLESS STEEL
■ Provides additional protection against corrosion
CONTINUOUS MAXIMUM FLOW RATES UP TO 9.0 GPM
CAN BE USED IN BOTH RESIDENTIAL AND
LIGHT COMMERCIAL APPLICATIONS
ENERGY STAR® QUALIFIED
OUTDOOR MODELS INCLUDE REMOTE CONTROL AS A STANDARD FEATURE
INDOOR MODELS INCLUDE BOTH A REMOTE CONTROL AND POWER CORD
AS STANDARD FEATURES
INDOOR MODELS
ATI-520H-N
ATI-520H-P
EASY-LINK UP TO 4 UNITS
■ With no additional parts or accessories needed
ELECTRONIC IGNITION-NO PILOT LIGHT
BUILT-IN DISPLAY SHOWS OPERATING TEMPERATURE ALONG WITH
DIAGNOSTIC AND ERROR CODES
LOW NOx EMISSIONS
COMPLIES WITH LEAD PLUMBING LAW
SAFETY FEATURES:
■ Air-Fuel Ratio (AFR) Sensor
■ Exhaust & Water Temperature Safety Control
■ Overheat Cutoff Fuse
ANSI Z21.10.3
CSA 4.3
INTERNAL FREEZE PROTECTION SYSTEM
POWER DIRECT VENT DESIGN
■ 4" Pipe Vents up to 50 Equivalent Feet or 3" Pipe Vents up to 25 Equivalent Feet
■ Uses Inexpensive PVC, CPVC, OR ABS Pipe for Intake and Exhaust (solid core only).
Canadian Installations Require ULCS636 Listed PVC or CPVC Pipe for Venting.
■ Category III Stainless Steel venting can also be used
ACCESSORIES
■
■
■
■
■
■
Remote Temperature Controller
Pipe Cover
Neutralizer Kit
Plumbing Installation Kits
PVC Intake Adaptor
Concentric Termination
WARRANTY
■ 12-year limited warranty on heat exchanger in residential applications
■ 5-year limited warranty on heat exchanger in commercial applications
■ 5-year warranty on all parts
Page 1 of 2
Revised March 2012
AOSRG46805
Residential / Light Commercial
Gas Tankless Water Heaters
INDOOR CONDENSING MODELS
GAS CONSUMPTION INPUT
MODEL
NUMBER
FUEL
TYPE
MINIMUM
BTU/H
MAXIMUM
BTU/H
INLET GAS PRESSURE
MINIMUM
W.C.
DIMENSIONS IN INCHES
MAXIMUM
W.C.
ENERGY
FACTOR
HOT/COLD
GAS CONN.
HEIGHT
WIDTH
DEPTH
0.91
25-3/5
18-1/2
12-2/5
0.91
25-3/5
18-1/2
12-2/5
APPROX.
SHIPPING
WEIGHT
(LBS)
All dimension in inches.
15-150 psi Water Pressure. 40 psi or above recommended for maximum flow.
18-1/2" (470mm)
12-1/2" (320mm)
12-1/2" (316mm)
3-1/2" (90mm)
Ø4" (102mm) Female
Male Ø4" (100.8mm)
3/4" (18.8mm)
25-1/2" (649mm)
2-3/4" (69.1mm) INTAKE
2-3/4" (71.8mm) EXHAUST
6-5/8" (168.4mm)
1/2" (12.5mm)
29-1/2" (751mm)
6-1/4" (161.5mm)
1-1/4" (29.2mm) COLD
GAS 6" (153.6mm)
120VAC 2-1/4" (58.2mm)
HOT 7-1/4" (182.1mm)
120VAC 8-1/2" (216.3mm)
4-5/8" (116.8mm) GAS
HOT 5-5/8" (142.2mm)
6-1/4" (159.1mm)
Condensate Drain Port
COLD 8-5/8" (220.6mm)
10-1/2" (266.8mm)
Condensate Drain Port
Flow Rate vs. Temperature Rise
50
Pressure Loss
120
45
100
40
35
80
30
25
60
20
40
15
10
20
5
0
0
20
40
60
80
100
Temperature Rise (°F)
120
140
Head Feet
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0
Pressure Loss (psi)
Flow Rate (gpm)
CLEARANCES: Top: 12”; Bottom: 12”; Front: 4”; Back: .05”; Sides: 3”
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
0
9.0 10.0
Flow Rate (gpm)
Set Temperature : 125 °F & lower
Set Temperature: 130 °F & Higher
For Technical Information call 1-877-737-2840. A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.
Revised March 2012
www.hotwater.com
Page 2 of 2
AOSRG46805